Abstract
Therapeutic options for recurrent adult granulosa cell tumors (AGCT) are limited. After examining the hormonal pathways involved in FOXL2-mutated granulosa cell tumor development, a novel treatment regimen was utilized for recurrent AGCT: a combination of an androgen receptor antagonist, a gonadotropin-releasing hormone receptor agonist, and an aromatase inhibitor for hormonal blockade. In this case series, seven patients at our institution were treated with bicalutamide 50 mg orally once daily, Leuprolide acetate 7.5 mg intramuscular (IM) injection every 4 weeks, and a daily oral aromatase inhibitor. These patients had recurrent AGCT with androgen receptor positive tumors and had failed prior aromatase inhibitor therapy. All patients had undergone multiple surgical resections and many cycles of chemotherapy. Patients were monitored for toxicities and for response to treatment. Of the seven patients receiving the triple therapy, six saw clinical benefit. Two patients demonstrated a partial response and four patients had stable disease. One patient had progressive disease on the regimen. For the two patients who had a partial response to the triple therapy, there was strong expression of the androgen receptor (AR) noted on tumor immunohistochemistry. This drug combination was well-tolerated except for severe hot flashes in one patient. In conclusion, the triple therapy combination of an androgen receptor antagonist, aromatase inhibitor, and GnRH agonist demonstrated measurable responses in patients with recurrent AGCTs after multiple previous treatments. A prospective clinical trial is planned to further investigate these findings.